There has been plenty of speculation about the Corvette Stingray ZR1 and Z06. There was even a Motor Trend report that that the Z06 would get an updated 7-liter with 600 horsepower and the ZL1 would get a 700-horsepower, 6.2-liter V-8. Well, apparently those “leaks” were intended to throw us off of the scent, as GM has just unveiled the powerplants and they are surprising, to say the least.

Under the hood of the Z06, you’ll get an updated version of the all-new 6.2-liter engine with an extra 90 horsepower, thanks to a new fuel-injection system, new software, aggressive cams and titanium exhaust system with a freer flow. The Z06 will use a six-speed automated manual transmission with no mention of a full-manual option.

The ZR1 is far and away the most unexpected change, as it will be the first Corvette since the 1950s to feature a six-cylinder engine. This twin-turbocharged 3.6-liter V-6 engine – yes, the same all-aluminum block found in the upcoming CTS Vsport – tuned to an incredible 640 horsepower.

While this 3.6-liter may sound like the same one that Caddy will use, keep in mind that the guts are fully modified to handle the 24 psi of pressure the turbochargers pump out. These modifications include: upgraded titanium pistons and connecting rods, revised software, updated cylinder heads and low-resistance bearings.

Just like the Stingray, all Chevy revealed with its first presser are the details on the engine. The Stingray Z06 and ZR1 will debut at the LA Auto Show, but we expect to see some leaked images as time goes on.

UPDATE: Sorry guys and gals, this one's completely fake... I was completely responsible for both the article and the press release. C'mon, a V-6 in a ZR1, I don't even know what I was thinking :). April Fools!!!

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